title: Josephson junction on one edge of a two dimensional topological insulator affected by magnetic impurity.
abstract: The current-phase relation in a Josephson junction formed by putting two s-wave superconductors on the same edge of a two dimensional topological insulator is investigated. We consider the case in which the junction length is finite and magnetic impurity exists. The similarities and differences with respect to a conventional Josephson junction are discussed. Both the 2π- and 4π-period current-phase relations (I2π(ϕ),I4π(ϕ)) are studied. There is a sharp jump at ϕ = π and ϕ = 2π for I2π and I4π, respectively, in the clean junction. For I2π, the sharp jump is robust against the impurity strength and distribution. However, for I4π, an impurity makes the jump at ϕ = 2π smooth. The critical (maximum) current Ic,2π of I2π is given and we find it will be increased by an asymmetrical distribution of the impurity.
authors.affiliation: Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China.
authors.forename: Shu-Feng
authors.initials: SF
authors.lastname: Zhang
authors.forename: Wei
authors.initials: W
authors.lastname: Zhu
authors.forename: Qing-Feng
authors.initials: QF
authors.lastname: Sun
mesh_terms: D000465:Algorithms; D004553:Electric Conductivity; D060526:Magnetic Fields; D012666:Semiconductors